1. Department of Periodontology, Academic Center for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, 1081 LA Amsterdam, The Netherlands
2. Department of Internal Medicine, Amsterdam University Medical Center (AUMC), University of Amsterdam and Vrije Universiteit Amsterdam, 1105 AZ Amsterdam, The Netherlands
3. Department of Internal Medicine, Spaarne Gasthuis, 2134 TM Hoofddorp, The Netherlands
4. Department of Oral Public Health, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, 1081 LA Amsterdam, The Netherlands
5. Royal Dutch Dental Association (KNMT), 3528 BB Utrecht, The Netherlands